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1.
Neuro Oncol ; 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38989697

RESUMEN

BACKGROUND: Managing non-functioning pituitary adenomas (NFPAs) is difficult due to limited drug treatments. Cabergoline's (CAB) effectiveness for NFPAs is debated. This study explores the role of HTR2B in NFPAs and its therapeutic potential. METHODS: We conducted screening of bulk RNA-sequencing data to analyze HTR2B expression levels in NFPA samples. In vitro and in vivo experiments were performed to evaluate the effects of HTR2B modulation on tumor growth and cell cycle regulation. Mechanistic insights into the HTR2B-mediated signaling pathway were elucidated using pharmacological inhibitors and molecular interaction assays. RESULTS: Elevated HTR2B expression was detected in NFPA samples, which was associated with increased tumor survival. Inhibition of HTR2B activity resulted in the suppression of tumor growth through modulation of the G2M cell cycle. The inhibition of HTR2B with PRX-08066 was found to block STAT3 phosphorylation and nuclear translocation by interfering with the Gαq/PLC/PKC pathway. A direct interaction between PKC-γ and STAT3 was critical for STAT3 activation. CAB was shown to activate pSTAT3 via HTR2B, reducing its therapeutic potential. However, the combination of an HTR2B antagonist with CAB significantly inhibited tumor cell proliferation in HTR2B-expressing pituitary tumor cell lines, a xenografted pituitary tumor model, and patient-derived samples. Analysis of patient-derived data indicated that a distinct molecular pattern characterized by upregulated HTR2B/PKC-γ and downregulated BTG2/GADD45A may benefit from combination treatment with CAB and PRX-08066. CONCLUSIONS: HTR2B is a potential therapeutic target for NFPAs, and its inhibition could improve CAB efficacy. A dual therapy approach may be beneficial for NFPA patients with high HTR2B expression.

2.
Toxicol Lett ; 399: 1-8, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38969027

RESUMEN

2-Methyl-4-nitroaniline (MNA), an intermediate in the synthesis of azo dyes, is widely distributed in various environmental media and organisms. Although there is speculation regarding MNA's potential to be hepatotoxic, the underlying mechanisms of its hepatotoxicity and its definitive diagnostic process remain largely unexplored. In this research. In the present study, we initially predicted the toxicity and possible toxic effect pathways of MNA using ProTox-II, and found that MNA binds to the PPARγ receptor (binding energy -6.118 kcal/mol) with a potential PPARγ agonist effect. Subsequently, in vivo exposure evaluation was conducted on Wistar rats to assess the impact of MNA after a 90-day exposure period, by detecting serum biochemical indexes, hematological indexes, urinary indexes, inflammatory factors, liver histopathological observations and liver tissue PPARγ mRNA expression. The results showed that MNA causes liver function abnormalities, liver histopathological changes and inflammatory response, along with a pronounced increase in PPARγ mRNA levels. This study suggests that the hepatotoxic mechanism of MNA may be related to its possible upregulation of PPARγ expression, increased liver dysfunction and inflammatory responses. Based on these results, the benchmark dose lower limit (BMDL) of 1.503 mg/kg for male Wistar rats was also established, providing a vital benchmark for determining the safety threshold of MNA. Our data highlight the hepatotoxic mechanism of MNA and contribute to a better understanding of its potential etiological diagnosis.

3.
PLoS One ; 19(7): e0307113, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39008477

RESUMEN

Understanding the extent of inflammation is crucial for early disease detection, monitoring disease progression, and evaluating treatment responses. Over the past decade, researchers have demonstrated the need to understand the extent of inflammation through qualitative or quantitative characterization of tissue viscoelasticity using different techniques. In this scientific review, an examination of research on the association between elasticity and Viscosity in diseases, particularly as tissue inflammation progresses, is conducted. A review of utilizing mechanical rheological models to characterize quantitative viscoelastic parameters of normal and inflamed tissues is also undertaken. Based on inclusion and exclusion criteria, we identified 14 full-text studies suitable for review out of 290 articles published from January 2000 to January 2024. We used PRISMA guidelines for the systematic review. In the review, three studies demonstrated the criterion used by the researchers in identifying the best rheological model. Eleven studies showed the clinical application of the rheological model in quantifying the viscoelastic properties of normal and pathological tissue. The review quantified viscoelastic parameters for normal and pathological tissue across various soft tissues. It evaluated the effectiveness of each viscoelastic property in distinguishing between normal and pathological tissue stiffness. Furthermore, the review outlined additional viscoelastic-related parameters for researchers to consider in future stiffness classification studies.


Asunto(s)
Elasticidad , Inflamación , Reología , Viscosidad , Humanos , Inflamación/patología , Modelos Biológicos
4.
Zhen Ci Yan Jiu ; 49(7): 767-776, 2024 Jul 25.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-39020496

RESUMEN

Stroke brings the pathological changes of brain tissues such as hematoma formation or ischemia and hypoxia, which leads to neuronal death and axon degeneration. Axon regeneration after its injury is mainly dependent on the surrounding microenvironment and the related proteins, including glial scar, myelin associated inhibitory factors, axon guidance molecules, and neurotrophic factors. All of them affect axon growth by regulating the morphology and orientation of growth cones, the synaptic stability, and the proliferation and differentiation of neural stem cells. This article summarizes the mechanism of acupuncture in regulating axon regeneration after stroke. Acupuncture inhibits glial scar formation, alleviates the inhibitory effects of its physical and chemical barriers on axon growth, reverses the inhibitory effects of myelin-related inhibitory factors on axon growth, and adjusts the level of axon guidance molecules to promote the proliferation and differentiation of neural stem cells and the regeneration of injured axons, and up-regulates neurotrophic factors. Eventually, post-stroke nerve injury can be ameliorated.


Asunto(s)
Terapia por Acupuntura , Axones , Regeneración Nerviosa , Accidente Cerebrovascular , Humanos , Animales , Axones/metabolismo , Axones/fisiología , Accidente Cerebrovascular/terapia , Accidente Cerebrovascular/metabolismo , Accidente Cerebrovascular/fisiopatología , Células-Madre Neurales/metabolismo
5.
Materials (Basel) ; 17(13)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38998312

RESUMEN

The production of aluminum alloy multi-lumen tubes primarily involves hot bending formation, a process where controlling thermal deformation quality is difficult. Specifically, the inner cavity wall of the tube is prone to bending instability defects under the bending stress field. To address these challenges in the bending deformation of aluminum alloy multi-lumen tubes, a multi-lumen liquid-filled bypass forming method is proposed in this paper. This study focuses on the 6063-T5 aluminum alloy double-lumen tube as the research object. The liquid-filled bending deformation behavior of the aluminum alloy double-lumen tube was investigated, and the deformation theory of the aluminum alloy double-lumen tube was studied. Through experimental and numerical simulation methods, the influence of support internal pressure, bending radius, and tube wall thickness on the liquid-filled bending deformation behavior of the double-lumen tube was examined. The results indicate that when the value of internal pressure was 7.5 MPa, the straightening of the outer wall was improved by 2.51%, the thinning rate of wall thickness was minimized, and the internal concave defect was effectively suppressed. The liquid-filled bending method provides a promising new approach for the integrated bending and forming of multi-lumen tubes.

6.
Diabetes Metab Syndr Obes ; 17: 2619-2625, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38974951

RESUMEN

Purpose: To examine the risk of type 2 diabetes mellitus in non-obese patients with pancreatic fatty infiltration through abdominal computed tomography (CT) quantitation. Patients and Methods: We carried out a retrospective analysis of abdominal CT and inpatient medical records of 238 inpatients from July 2019 to April 2021. The patients were divided into a normal non-obese group (BMI < 25, n = 135) and diabetic non-obese group (BMI < 25, n = 103). Abdominal CT-related parameters included body width; mean CT values of the pancreas, liver, and spleen; difference between pancreas and spleen CT values (P-S); pancreas-to-spleen attenuation ratio (P/S); and liver-to-spleen attenuation ratio (L/S). Logistic regression was used to estimate the risk factors for comorbid diabetes in a non-obese population. Results: The P-values of the pancreas CT value, P-S, P/S, body width, and L/S were all <0.05 and correlated to comorbid diabetes in non-obese patients. Worsening pancreatic fatty infiltration increased the risk of developing diabetes. Using a P/S of 1.0 as reference, every successive decrease in this ratio by 0.1 increases patient risk by 3.981, 4.452, 6.037, and 12.937 times. Conclusion: The risk of developing type 2 diabetes mellitus in non-obese patients increases with the degree of pancreatic fatty infiltration as assessed by CT.

7.
CNS Neurosci Ther ; 30(6): e14811, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38923840

RESUMEN

BACKGROUND: To date, most existing models for predicting neuromyelitis optica spectrum disorder (NMOSD) are based primarily on clinical characteristics. Blood-based NMOSD severity and prognostic predictive immune- and inflammation-related biomarkers are needed. We aimed to investigate the associations between plasma inflammatory biomarkers and relapse and attack severity in NMOSD. METHODS: This two-step, single-center prospective cohort study included discovery and validation cohorts. We quantified 92 plasma inflammatory proteins by using Olink's proximity extension assay and identified differentially expressed proteins in the relapse group (relapse within 1 year of follow-up) and severe attack group. To define a new molecular prognostic model, we calculated the risk score of each patient based on the key protein signatures and validated the results in the validation cohort. RESULTS: The relapse prediction model, including FGF-23, DNER, GDNF, and SLAMF1, predicted the 1-year relapse risk. The severe attack prediction model, including PD-L1 and MCP-2, predicted the severe clinical attack risk. Both the relapse and severe attack prediction models demonstrated good discriminative ability and high accuracy in the validation cohort. CONCLUSIONS: Our discovered biomarker signature and prediction models may complement current clinical risk stratification approaches. These inflammatory biomarkers could contribute to the discovery of therapeutic interventions and prevent NMOSD progression.


Asunto(s)
Biomarcadores , Neuromielitis Óptica , Recurrencia , Humanos , Neuromielitis Óptica/sangre , Neuromielitis Óptica/diagnóstico , Femenino , Biomarcadores/sangre , Masculino , Adulto , Estudios Prospectivos , Persona de Mediana Edad , Estudios de Cohortes , Índice de Severidad de la Enfermedad , Inflamación/sangre , Inflamación/diagnóstico , Pronóstico
8.
Mol Cell ; 84(12): 2255-2271.e9, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38851186

RESUMEN

The mechanisms and timescales controlling de novo establishment of chromatin-mediated transcriptional silencing by Polycomb repressive complex 2 (PRC2) are unclear. Here, we investigate PRC2 silencing at Arabidopsis FLOWERING LOCUS C (FLC), known to involve co-transcriptional RNA processing, histone demethylation activity, and PRC2 function, but so far not mechanistically connected. We develop and test a computational model describing proximal polyadenylation/termination mediated by the RNA-binding protein FCA that induces H3K4me1 removal by the histone demethylase FLD. H3K4me1 removal feeds back to reduce RNA polymerase II (RNA Pol II) processivity and thus enhance early termination, thereby repressing productive transcription. The model predicts that this transcription-coupled repression controls the level of transcriptional antagonism to PRC2 action. Thus, the effectiveness of this repression dictates the timescale for establishment of PRC2/H3K27me3 silencing. We experimentally validate these mechanistic model predictions, revealing that co-transcriptional processing sets the level of productive transcription at the locus, which then determines the rate of the ON-to-OFF switch to PRC2 silencing.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Regulación de la Expresión Génica de las Plantas , Silenciador del Gen , Histonas , Proteínas de Dominio MADS , Complejo Represivo Polycomb 2 , ARN Polimerasa II , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Histonas/metabolismo , Histonas/genética , ARN Polimerasa II/metabolismo , ARN Polimerasa II/genética , Complejo Represivo Polycomb 2/metabolismo , Complejo Represivo Polycomb 2/genética , Proteínas de Dominio MADS/genética , Proteínas de Dominio MADS/metabolismo , Transcripción Genética , Poliadenilación , Histona Demetilasas/metabolismo , Histona Demetilasas/genética , Terminación de la Transcripción Genética , Cromatina/metabolismo , Cromatina/genética , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética
9.
Front Neurol ; 15: 1402129, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38938782

RESUMEN

Objective: There is currently a lack of evidence in evidence-based medicine regarding acupuncture treatment for experimental intracerebral hemorrhage (ICH). The aim of this study was to systematically evaluate the efficacy of acupuncture treatment for experimental ICH based on neurological function scores and brain water content (BWC). Methods: Eight mainstream Chinese and English databases were searched. Outcome measures included neurological function scores and BWC, and subgroup analysis was conducted based on study characteristics. Results: A total of 32 studies were included. Meta-analysis results indicated that compared to the control group, the acupuncture group showed significant reductions in mNSS (MD = -3.16, p < 0.00001), Bederson score (MD = -0.99, p < 0.00001), Longa score (MD = -0.54, p < 0.0001), and brain water content (MD = -5.39, p < 0.00001). Subgroup analysis revealed that for mNSS, the autologous blood model (MD = -3.36) yielded better results than the collagenase model (MD = -0.92, p < 0.00001), and simple fixation (MD = -3.38) or no fixation (MD = -3.39) was superior to sham acupuncture (MD = -0.92, p < 0.00001). For BWC, the autologous blood model (MD = -7.73) outperformed the collagenase model (MD = -2.76, p < 0.00001), and GV20-GB7 (MD = -7.27) was more effective than other acupuncture points (MD = -2.92, p = 0.0006). Conclusion: Acupuncture significantly improves neurological deficits and brain edema in experimental ICH. Acupuncture at GV20 - GB7 is more effective than at other points. These findings support further studies to translate acupuncture into clinical treatment for human ICH. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023435584.

10.
Int Immunopharmacol ; 134: 112159, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38692018

RESUMEN

CONTEXT: Medical treatment plays a critical role in pituitary neuroendocrine tumour (PitNET) treatment. Dopamine agonists and somatostatin receptor agonists are the only known drugs for effectively treating PitNET. Thus, the identification of potential therapeutic targets and drugs is urgently needed. OBJECTIVE: To discover potential drugs that can suppress PitNET growth and to further investigate the underlying mechanism involved. METHODS: High-throughput drug screening of primary cultures of 17 patient-derived PitNETs was performed to identify potential therapeutic compounds. Cell viability assays, Western blot analysis and flow cytometry were used to investigate pituitary neuroendocrine tumour cell lines and patient-derived PitNET cultures in vitro. In vivo drug efficacy was examined in a mouse xenograft model. RESULTS: Seventeen primary PitNET samples were collected for high-throughput drug screening, and a class of copper ionophores that can effectively inhibit cell growth, such as zinc pyrithione, elesclomol, and disulfiram (DSF), was identified. Subsequent experiments initially validated the dose-dependent cell growth-suppressing effect of these copper ionophores on AtT20, GH3, and MMQ cells and several primary PitNET cell lines. Moreover, we confirmed that the cytotoxic effect of DSF depends on the presence of copper. Additionally, we determined that cell death occurs via cuproptosis, with events such as Fe-S cluster protein loss, dihydrolipoyl transacetylase oligomerization and heat shock protein 70 upregulation. Finally, we verified the cytotoxic effects of DSF in vivo. CONCLUSION: The present study revealed copper ionophores as a potential class of drugs for PitNET treatment. DSF induced PitNET cell death via cuproptosis and might be a promising option for PitNET therapy.


Asunto(s)
Antineoplásicos , Disulfiram , Tumores Neuroendocrinos , Neoplasias Hipofisarias , Ensayos Antitumor por Modelo de Xenoinjerto , Disulfiram/farmacología , Disulfiram/uso terapéutico , Animales , Neoplasias Hipofisarias/tratamiento farmacológico , Neoplasias Hipofisarias/patología , Humanos , Tumores Neuroendocrinos/tratamiento farmacológico , Tumores Neuroendocrinos/patología , Línea Celular Tumoral , Ratones , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Femenino , Masculino , Persona de Mediana Edad , Ratones Desnudos , Proliferación Celular/efectos de los fármacos , Adulto , Supervivencia Celular/efectos de los fármacos
11.
Heliyon ; 10(9): e29605, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38707478

RESUMEN

Objective: The predictive value of serum tumor markers (STMs) in assessing epidermal growth factor receptor (EGFR) mutations among patients with non-small cell lung cancer (NSCLC), particularly those with non-stage IA, remains poorly understood. The objective of this study is to construct a predictive model comprising STMs and additional clinical characteristics, aiming to achieve precise prediction of EGFR mutations through noninvasive means. Materials and methods: We retrospectively collected 6711 NSCLC patients who underwent EGFR gene testing. Ultimately, 3221 stage IA patients and 1442 non-stage IA patients were analyzed to evaluate the potential predictive value of several clinical characteristics and STMs for EGFR mutations. Results: EGFR mutations were detected in 3866 patients (57.9 %) of all NSCLC patients. None of the STMs emerged as significant predictor for predicting EGFR mutations in stage IA patients. Patients with non-stage IA were divided into the study group (n = 1043) and validation group (n = 399). In the study group, univariate analysis revealed significant associations between EGFR mutations and the STMs (carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC), and cytokeratin-19 fragment (CYFRA21-1)). The nomogram incorporating CEA, CYFRA 21-1, pathology, gender, and smoking history for predicting EGFR mutations with non-stage IA was constructed using the results of multivariate analysis. The area under the curve (AUC = 0.780) and decision curve analysis demonstrated favorable predictive performance and clinical utility of nomogram. Additionally, the Random Forest model also demonstrated the highest average C-index of 0.793 among the eight machine learning algorithms, showcasing superior predictive efficiency. Conclusion: CYFRA21-1 and CEA have been identified as crucial factors for predicting EGFR mutations in non-stage IA NSCLC patients. The nomogram and 8 machine learning models that combined STMs with other clinical factors could effectively predict the probability of EGFR mutations.

12.
Biology (Basel) ; 13(5)2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38785804

RESUMEN

The pathogenesis of inflammatory bowel disease (IBD) is still unknown. Mesenteric lymphatics (MLs), which are closely related to the intestine in both anatomy and physiology, have been suggested to be involved in IBD. In the present study, we aim to investigate the effects of ML immune cells on IBD and explore the potential associated mechanisms. Acute colitis was induced in rats using dextran sulfate sodium salt (DSS). Mesenteric lymphangiogenesis, ML stenosis, and dilation were observed, with an increased proportion of MLB cells in DSS-induced colitis rats. The adoptive transfer of B cells isolated from ML (MLB) was employed to investigate their effects on colitis. MLB cells derived from DSS-induced colitis rats exhibited a higher propensity to migrate to the intestine. The proportion of colonic T cells was altered, along with the aggravated colitis induced by the adoptive transfer of MLB cells derived from DSS-induced colitis rats. RNA sequencing revealed increased Cxcr5 expression in MLB cells from colitis rats, while real-time PCR indicated an upregulation of its ligand Cxcl13 in the colon of colitis rats. These findings suggest that MLB cells may migrate to the intestine and aggravate colitis. In summary, colonic T cells respond to MLB cells from colitis rats, and MLB cells aggravate DSS-induced colitis via the CXCR5-CXCL13 axis.

13.
Genome Med ; 16(1): 60, 2024 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-38658971

RESUMEN

BACKGROUND: Pituitary neuroendocrine tumors (PitNETs) are common gland neoplasms demonstrating distinctive transcription factors. Although the role of immune cells in PitNETs has been widely recognized, the precise immunological environment and its control over tumor cells are poorly understood. METHODS: The heterogeneity, spatial distribution, and clinical significance of macrophages in PitNETs were analyzed using single-cell RNA sequencing (scRNA-seq), bulk RNA-seq, spatial transcriptomics, immunohistochemistry, and multiplexed quantitative immunofluorescence (QIF). Cell viability, cell apoptosis assays, and in vivo subcutaneous xenograft experiments have confirmed that INHBA-ACVR1B influences the process of tumor cell apoptosis. RESULTS: The present study evaluated scRNA-seq data from 23 PitNET samples categorized into 3 primary lineages. The objective was to explore the diversity of tumors and the composition of immune cells across these lineages. Analyzed data from scRNA-seq and 365 bulk RNA sequencing samples conducted in-house revealed the presence of three unique subtypes of tumor immune microenvironment (TIME) in PitNETs. These subtypes were characterized by varying levels of immune infiltration, ranging from low to intermediate to high. In addition, the NR5A1 lineage is primarily associated with the subtype characterized by limited infiltration of immune cells. Tumor-associated macrophages (TAMs) expressing CX3CR1+, C1Q+, and GPNMB+ showed enhanced contact with tumor cells expressing NR5A1 + , TBX19+, and POU1F1+, respectively. This emphasizes the distinct interaction axes between TAMs and tumor cells based on their lineage. Moreover, the connection between CX3CR1+ macrophages and tumor cells via INHBA-ACVR1B regulates tumor cell apoptosis. CONCLUSIONS: In summary, the different subtypes of TIME and the interaction between TAM and tumor cells offer valuable insights into the control of TIME that affects the development of PitNET. These findings can be utilized as prospective targets for therapeutic interventions.


Asunto(s)
Macrófagos , Tumores Neuroendocrinos , Neoplasias Hipofisarias , Análisis de la Célula Individual , Transcriptoma , Microambiente Tumoral , Humanos , Tumores Neuroendocrinos/genética , Tumores Neuroendocrinos/patología , Tumores Neuroendocrinos/inmunología , Tumores Neuroendocrinos/metabolismo , Neoplasias Hipofisarias/genética , Neoplasias Hipofisarias/inmunología , Neoplasias Hipofisarias/patología , Neoplasias Hipofisarias/metabolismo , Microambiente Tumoral/inmunología , Microambiente Tumoral/genética , Animales , Ratones , Macrófagos/metabolismo , Macrófagos/inmunología , Macrófagos Asociados a Tumores/metabolismo , Macrófagos Asociados a Tumores/inmunología , Regulación Neoplásica de la Expresión Génica , Perfilación de la Expresión Génica , Fenotipo , Apoptosis/genética , Linaje de la Célula/genética
14.
Nat Microbiol ; 9(5): 1244-1255, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38649414

RESUMEN

Carbapenem-resistant Acinetobacter baumannii infections have limited treatment options. Synthesis, transport and placement of lipopolysaccharide or lipooligosaccharide (LOS) in the outer membrane of Gram-negative bacteria are important for bacterial virulence and survival. Here we describe the cerastecins, inhibitors of the A. baumannii transporter MsbA, an LOS flippase. These molecules are potent and bactericidal against A. baumannii, including clinical carbapenem-resistant Acinetobacter baumannii isolates. Using cryo-electron microscopy and biochemical analysis, we show that the cerastecins adopt a serpentine configuration in the central vault of the MsbA dimer, stalling the enzyme and uncoupling ATP hydrolysis from substrate flipping. A derivative with optimized potency and pharmacokinetic properties showed efficacy in murine models of bloodstream or pulmonary A. baumannii infection. While resistance development is inevitable, targeting a clinically unexploited mechanism avoids existing antibiotic resistance mechanisms. Although clinical validation of LOS transport remains undetermined, the cerastecins may open a path to narrow-spectrum treatment modalities for important nosocomial infections.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Antibacterianos , Proteínas Bacterianas , Lipopolisacáridos , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/metabolismo , Lipopolisacáridos/metabolismo , Animales , Infecciones por Acinetobacter/microbiología , Infecciones por Acinetobacter/tratamiento farmacológico , Ratones , Antibacterianos/farmacología , Proteínas Bacterianas/metabolismo , Transporte Biológico , Pruebas de Sensibilidad Microbiana , Humanos , Microscopía por Crioelectrón , Carbapenémicos/farmacología , Carbapenémicos/metabolismo , Modelos Animales de Enfermedad , Femenino , Transportadoras de Casetes de Unión a ATP
15.
Materials (Basel) ; 17(8)2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38673165

RESUMEN

The low-temperature fatigue crack propagation rate of 925A steel, as a rudder steel for polar special ships, has a crucial impact on the evaluation of the fatigue strength of polar ships. The purpose of this article is to study the fatigue crack propagation rate of 925A steel under different low-temperature conditions from room temperature (RT) to -60 °C. The material was subjected to fatigue crack propagation tests and stress intensity factor tests. The experimental tests were conducted according to the Chinese Standard of GB/T6398-2017. The results show that as the temperature decreases, the lifespan of 925A increases. Within a certain stress intensity factor, as the temperature decreases, the fatigue crack propagation rate decreases. At -60 °C, it exhibits ductile fracture; within normal polar temperatures, it can be determined that 925A meets the requirements for low-temperature fatigue crack propagation rates in polar regions. However, in some extreme polar temperatures below -60 °C, preventing brittle failure becomes a key focus of fatigue design. Finally, the fatigue crack propagation behavior at the microscale of 925A steel at low temperatures was described using fracture morphology. The experimental data can provide reference for the design of polar ships to further resist low-temperature fatigue and cold brittle fracture.

16.
Pestic Biochem Physiol ; 200: 105842, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38582604

RESUMEN

Chemical sensing systems are vital in the growth and development of insects. Orius sauteri (Poppius) (Hemiptera: Anthocoridae) is an important natural enemy of many pests. The molecular mechanism of odorant binding proteins (OBPs) binding with common insecticides is still unknow in O. sauteri. In this study, we expressed in vitro OsauOBP8 and conducted fluorescence competition binding assay to investigate the function of OsauOBP8 to insecticides. The results showed that OsauOBP8 could bind with four common insecticides (phoxim, fenitrothion, chlorpyrifos, deltamethrin). Subsequently, we used molecular docking to predict and obtained candidate six amino acid residues (K4, K6, K13, R31, K49, K55) and then mutated. The result showed that three key residues (K4, K6, R31) play important role in OsauOBP8 bound to insecticides. Our study identified the key binding sites of OsauOBP8 to insecticides and help to better understand the molecular mechanism of OBPs to insecticides in O. sauteri.


Asunto(s)
Heterópteros , Insecticidas , Receptores Odorantes , Animales , Simulación del Acoplamiento Molecular , Receptores Odorantes/genética
17.
J Med Chem ; 67(9): 7373-7384, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38646851

RESUMEN

Natural product evodiamine is a multitargeting antitumor lead compound. However, clinical development of evodiamine derivatives was hampered by poor water solubility and limited in vivo antitumor potency. Herein, a series of evodiamine-glucose conjugates were designed by additional targeting glucose transporter-1 (GLUT1). Compared with the lead compound, conjugate 8 exhibited obvious enhancement in water solubility and in vivo antitumor efficacy. Furthermore, the effect of GLUT1 targeting also led to lower cytotoxicity to normal cells. Antitumor mechanism studies manifested that conjugate 8 acted by Top1/Top2 dual inhibition, apoptosis induction, and G2/M cell cycle arrest, which selectively targeted tumor cells with a high expression level of GLUT1. Thus, evodiamine-glucose conjugates showed promising features as potential antitumor agents.


Asunto(s)
Antineoplásicos , Apoptosis , Diseño de Fármacos , Glucosa , Quinazolinas , Quinazolinas/farmacología , Quinazolinas/química , Quinazolinas/síntesis química , Humanos , Animales , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Glucosa/metabolismo , Apoptosis/efectos de los fármacos , Ratones , Transportador de Glucosa de Tipo 1/antagonistas & inhibidores , Transportador de Glucosa de Tipo 1/metabolismo , Relación Estructura-Actividad , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Ratones Desnudos , Ratones Endogámicos BALB C
18.
J Phys Chem A ; 128(18): 3557-3563, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38666353

RESUMEN

Azido-tetrazolo tautomerizations between azido N-heteroaromatic compounds and tetrazole-fused energetic materials can produce a new generation of high-energy density compounds. Density functional theory (DFT) computations are performed to explore the relationship between reaction barriers and electron densities of bonding N atoms, i.e., the terminal N1 and heterocyclic N2 atoms, for six reported tautomerizations. The results reveal four linear correlations between reverse reaction barriers (Gr) and the electron densities of N1 and N2 atoms in the product. N1 electron density (ρN1) and N-N bond polarity, as measured by the difference between the electron densities on the two N atoms (ΔρN = ρN1 - ρN2) in products, are inversely proportional to the reverse reaction barriers. They are also proportional to the energy barrier differences between the forward and reverse reactions (ΔG = Gf - Gr). Polar solvents, including DMSO, water, and acetone, can effectively increase the reverse reaction barriers (Gr) by improving the stability of products. This regularity is further confirmed by its application to four additional tautomerizations and can be used to screen out unfavorable azido-tetrazolo tautomerization reactions and increase the success rate of such synthesis.

19.
Ther Adv Neurol Disord ; 17: 17562864241239117, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38616782

RESUMEN

Multiple sclerosis (MS) was defined as a rare disease in China due to its low prevalence. For a long time, interferon ß was the only approved disease-modifying therapy (DMT). Since the first oral DMT was approved in 2018, DMT approval accelerated, and seven DMTs were approved within 5 years. With an increasing number of DMTs being prescribed in clinical practice, it is necessary to discuss the standardized MS treatment algorithms depending on the disease activity and DMT availability. In this review paper, more than 20 Chinese experts in MS have reviewed the therapeutic progress of MS in China and worldwide and discussed algorithms for treating relapsing MS (RMS) based on the available DMTs in China, providing insights for establishing the standardized RMS treatment algorithms in this country.


Treatment algorithms of relapsing multiple sclerosis in China In this review paper, more than 20 Chinese experts in MS have reviewed the therapeutic progress of MS in China and worldwide and discussed algorithms for treating relapsing MS (RMS) based on the available DMTs in China, providing insights for establishing the standardized RMS treatment algorithms in this country: 1) CIS and RRMS account for more than 90% of the MS patients and most of them are mild to moderate; 2) MS patients should initiate DMT treatments as soon as the disease has been diagnosed in order to reduce the risk of disease progression; 3) Patients who have been diagnosed with MS should start treatment with fundamental DMTs unless the disease course has been highly active; 4) MAGNIMS score may be a suitable and simplified assessment tool for measuring treatment response to DMTs; 5) Patients treated with corticosteroids and NSIS should be switched to the standardized DMT treatment during remission in accordance with disease activity.

20.
Technol Cancer Res Treat ; 23: 15330338241242654, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38584413

RESUMEN

Purpose: Deep learning (DL) is widely used in dose prediction for radiation oncology, multiple DL techniques comparison is often lacking in the literature. To compare the performance of 4 state-of-the-art DL models in predicting the voxel-level dose distribution for cervical cancer volumetric modulated arc therapy (VMAT). Methods and Materials: A total of 261 patients' plans for cervical cancer were retrieved in this retrospective study. A three-channel feature map, consisting of a planning target volume (PTV) mask, organs at risk (OARs) mask, and CT image was fed into the three-dimensional (3D) U-Net and its 3 variants models. The data set was randomly divided into 80% as training-validation and 20% as testing set, respectively. The model performance was evaluated on the 52 testing patients by comparing the generated dose distributions against the clinical approved ground truth (GT) using mean absolute error (MAE), dose map difference (GT-predicted), clinical dosimetric indices, and dice similarity coefficients (DSC). Results: The 3D U-Net and its 3 variants DL models exhibited promising performance with a maximum MAE within the PTV 0.83% ± 0.67% in the UNETR model. The maximum MAE among the OARs is the left femoral head, which reached 6.95% ± 6.55%. For the body, the maximum MAE was observed in UNETR, which is 1.19 ± 0.86%, and the minimum MAE was 0.94 ± 0.85% for 3D U-Net. The average error of the Dmean difference for different OARs is within 2.5 Gy. The average error of V40 difference for the bladder and rectum is about 5%. The mean DSC under different isodose volumes was above 90%. Conclusions: DL models can predict the voxel-level dose distribution accurately for cervical cancer VMAT treatment plans. All models demonstrated almost analogous performance for voxel-wise dose prediction maps. Considering all voxels within the body, 3D U-Net showed the best performance. The state-of-the-art DL models are of great significance for further clinical applications of cervical cancer VMAT.


Asunto(s)
Aprendizaje Profundo , Radioterapia de Intensidad Modulada , Neoplasias del Cuello Uterino , Femenino , Humanos , Radioterapia de Intensidad Modulada/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Dosificación Radioterapéutica , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/radioterapia , Estudios Retrospectivos , Órganos en Riesgo
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